Melismania

In music, melisma, commonly known as "vocal runs" or simply "runs," is the technique of changing the note (pitch) of a single syllable of text while it is being sung. Music sung in this style is referred to as melismatic, as opposed to syllabic, where each syllable of text is matched to a single note. A common example of melisma, or the singing of several notes sung to one syllable of text, is the Gregorian chant. For an example of syllabic singing, think of the Beatles’ “Penny Lane”:

In Penny Lane there is a barber showing photographs
Of every head he’s had the pleasure to have known
And all the people that come and go
Stop and say hello

While melismatic singing is quite common in popular music, few singers have used it, or are able to use it, tastefully. Nelson George, in The Death of Rhythm and Blues, refers to Sam Cooke (pictured) as a popular singer who effortlessly used melisma to marvelous effect:

No analysis . . . can capture the naturalness of Cooke’s sound. There was something ingratiating about his voice that entranced listeners and inspired a whole generation of male vocalists to try to approximate his supple sensuality and flowing melisma. (These would include David Ruffin, Johnnie Taylor, Otis Redding, Bobby Womack, Lou Rawls, and Jerry Butler.) (79)

Think of Cooke’s use of melisma with the monosyllabic word “You” in his hit “You Send Me.”

However, in popular singers less gifted than Sam Cooke, excessive (over) use of melisma results in melismania, defined by Michael Jarrett as

an obsessive compulsive disorder characterized by multiplying the notes sung to every syllable of text; melisma taken to excess.... melismania
. . . seeks to manufacture authenticity—to signify belief in the face of unbelief—through intense virtuosity . . . it creates rampant “affective inflation” that subverts its own efforts.... melismania is a particularly audible expression of what Lawrence Grossberg calls "sentimental inauthenticity." (82-83)

Melismania is variously known as “Mariah Carey Syndrome” or “Whitney Houston Syndrome,” although among Caucasians it is known as “Boltonism.”